48 Key to Families of North American Insects. 



11. Discal cell of both wings absent, neuration of the two sexes usually different, 

 apical veins few. (LEPTOCER1DM part; Banks, 1907) (Molanna). 



Discal cell of fore wings present ....................................... 12 



12. Middle tibiae with two spurs; discal cell of hind wings almost always open or 

 absent, only the upper branch of the radial sector forked, only the first 

 apical fork present; joints of maxillary palpi uniform; antennae long and 

 slender. (Lept6cerus) ............................... LEPTOCERUXE 



Middle tibiae usually with four spurs; discal cell of hind wings closed, both 

 branches of radial sector of fore wings forked, at least the first and second 

 apical forks present; basal joint of antennae large. (Nerophilus.) 



ODONTOCERUXE 



ORDER LEPEDOPTERA. 



(PSYCHE, GLOSS AT A.) 



Rather large, sometimes small or very large insects; wings and 

 body thickly clothed with scales that form a color pattern, these 

 rarely restricted to certain portions or absent in a very few unusual 

 forms; antennae long, many-jointed, variously modified; ocelli 

 sometimes present; mouthparts suctorial, when not in use coiled 

 under the head, the mandibles incorporated into an un jointed 

 tongue, which may be occasionally wanting; prothorax small; 

 wings large, membranous, similar, the fore pair somewhat longer; 

 venation complete, but not complex, few crossveins; legs similar, 

 tarsi ordinarily five-jointed; no cerci. Metamorphosis very great; 

 larvee with biting mouth-parts, usually caterpillar-like, and with 

 paired false-legs on some of the abdominal segments in addition to 

 three thoracic pairs; Iarva3 almost without exception plant- 

 feeders. Moths, Butterflies and Skippers. 



1. Antennas simple or variously modified (PI. 10, figs. 216, 224, 229), only rarely 

 swollen at the tip, and in such cases a frenulum is present; most forms with 

 a frenulum, the subcosta of the hind wing either but little arched at the 

 base or there is a large area between it and the fore margin of the wing; 

 wings at rest overlapping the abdomen or horizontally outspread; body 



often relatively stout. Moths. (HETEROCERA!) 2 



Antennae knobbed at the tip or thickened a little before the tip (PI. 10, figs. 

 219, 220, 237), without pectinations, projecting processes or conspicuous 

 arrangements of hairs; hind wings without a frenulum, but with the sub- 

 costa strongly arched forward at the base; at least the fore wings erect 

 when at rest. Butterflies and Skippers. (RHOPALOCERA, PAPILION- 

 OlDEA.) 97 



